Installing on separate drive from Windows in UEFI

I've just built a new desktop with two SSDs, one for Windows 8 and the other for OpenSUSE 13.1 (for dual-boot). Unfortunately, GRUB2 refused to install because the drive containing the /boot/efi partition didn't have a GUID Partition Table. Finding no option to create one, I booted back into Windows, shrank its partition, then went back into OpenSUSE install to put my /boot/efi on the newly freed space (after partitioning it to FAT). But the installer still complained of not having a GPT. How can Windows boot from the drive if there's no GPT?

Is there any way to get this dual-boot to work? And without touching the existing Windows installation if at all possible.

P.S. I can't set by BIOS to any sort of legacy mode. It's UEFI-only.